The present invention relates to a syringe-attached topical anesthetic dispenser. Syringes are employed millions of times daily all over the world to inject medicines into people as well as animals. Many times, injections are made in areas of the body that are somewhat less sensitive to pain. Other locations of the body where injections are contemplated are significantly more sensitive to pain and the patient feels a pinching sensation that may be quite painful as the syringe needle is inserted beneath the skin. Such areas include, for example, areas of the face such as the forehead as well as the lips.
Use of cosmetic injections into the face of a patient has become more and more common. Thus, for example, a chemical known by the Trademark Botox® is often injected into the face, particularly into a patient's forehead, to paralyze the subcutaneous muscles and temporarily eliminate visible wrinkles in the forehead. Such injections typically last several months at most and must be repeated over and over again, periodically, to maintain the non-wrinkled appearance.
Similarly, filler materials are often used, for example, within a patient's lips, to expand their size in keeping with the desires of the patient. Such dermal fillers include those sold under the Trademarks Juvederm®, Restylane® and Radiesse®.
When such chemicals are injected, typically to reduce pain associated with such injections, two options are employed. A first option is the use of a topical numbing cream applied to the area where the injection will take place. Typically, topical numbing creams require 40 minutes to 1 hour with occlusion to successfully numb the skin to a sufficient degree to render the subsequent injections painless. The second technique involves the use of numbing medicines such as Lidocaine®. However, the use of numbing medicines such as Lidocaine® is less preferred because it also requires needle injection through the skin which is not only painful, but can also distort the surrounding area, thereby making determination of the amount of filler to be subsequently placed more difficult. Additionally, injection of Lidocaine® may dilute the particles of subsequently injected Botox® making it easier for the Botox® substance to travel to distant locations and paralyze muscles the patient did not want to have paralyzed.
Additional methods of pre-injection cooling of the skin and associated tissues are also employed. For example, plain ice or ice-packed devices may be placed onto the skin and held there for a short period of time to numb the skin. Use of ice or ice-packed devices is inefficient and initially painful for the patient. Such devices must be placed onto the skin and held there for a short time and then must be removed with one hand and moved away from the patient by passing to an assistant or using some other technique. When these techniques are employed, often the physician is holding the ice pack which causes the physician's hand to be cooled and reduces effectiveness of the use of that hand. When the physician is injecting cosmetic medicines, one hand is used to work the syringe and the other is used to tense the skin, that is, to move the skin away from the muscle or palpate a bony landmark to aid in locating the proper place to inject the medicine. Use of ice can be messy and cold water resulting from melting of the ice can drip over the area to be injected. Use of ice, whether exposed or packed, limits the effectiveness of the physician who needs to have both hands available for the injection as explained above.
Another way to cool the area of the injection is to use a device consisting of a hose attached to an air cooling machine that blows cold air at the face. One such device is known by the Trademark Smartcool®. Such devices are expensive and often the patient complains that, as the cold air is blown at the face, it takes their breath away as quickly moving air rushes by their nose. Additionally, the surface area cooled by a Smartcool® device is often significantly greater than necessary to numb an anticipated injection.
Each of these prior art techniques used preliminary to an injection in a sensitive area of a patient such as on the face has its problems as explained above. The present invention was developed, keeping these problems in mind, and in an effort to provide a new technique to prepare a sensitive area of the human body to receive a cosmetic injection while avoiding messiness, pain, inconvenience, and expense. It is with these thoughts in mind that the present invention was developed.
Applicant is aware of the following prior art references:
U.S. Pat. No. 3,605,742 to Tibbs teaches a painless injection device which includes means for spraying a cooling fluid onto an injection site to numb the area prior to injection. The Tibbs device is extremely cumbersome including a large housing enclosing a syringe as well as the numbing device. An additional problem with Tibbs is that the needle path is not visible until the mechanism latch is released to expose the syringe bottom and attached needle. The actual depth of penetration of the needle appears to be set by the action of a spring which is not a sufficiently precise enough structure to allow placement of substances such as Botox® medicament or subcutaneous fillers. Additionally, the Tibbs device is clumsy since it has one depressor mechanism to express the syringe from the housing using a spring device and then a further attachment to the plunger end to deliver the medicament into the tissues. This may lead to imprecise placement of either the needle tip location or the desired depth of medicament dispersal, or both.
U.S. Pat. No. 4,725,265 to Sairenji discloses a syringe having an attached cooling gas injection nozzle for injecting a cooling gas onto skin where an injection is to take place. The gas is a vapo-coolant and the device includes a retractable rigid nozzle that is spring activated and serves as a conduit for spraying the vapo-coolant. The spring activation of the Sairenji device requires a second hand to disengage the downward position of the nozzle. Furthermore, Sairenji discloses a chamber into which the desired medicament is filled for injection into the patient, rather than a pre-filled disposable syringe. The Sairenji device is not practical for use where multiple sequential injections in spaced locations are contemplated. This is because all of the actions necessary to cause dispensing of the vapo-coolant then the injection make the Sairenji device extremely cumbersome and complicated.
U.S. Pat. No. 5,236,419 to Seney discloses a syringe including a distal portion containing a freezable chemical designed to engage the surface of the skin where an injection is to take place to cool that portion of the skin. Seney also discloses that it is known in the prior art to spray ethyl chloride onto a location of the skin as a topical anesthetic. However, Seney fails to teach or suggest dispensing a topical anesthetic by a device attached to a disposable syringe in the manner contemplated by the present invention.
U.S. Pat. No. 6,312,412 to Saied et al. discloses an apparatus and method for painless intramuscular or subcutaneous injections. In the Saied et al. device, a numbing agent is injected subcutaneously using a needle. The present invention improves upon the Saied et al. device by providing a topical dispensing of a numbing agent so that the pain inflicted on the patient by injecting the numbing agent is completely eliminated.
U.S. Pat. No. 6,936,028 to Hommann et al. discloses a cooling device for an injection apparatus. The Hommann et al. device is somewhat similar to that of Seney as including a cooling element surrounding the location where the syringe will be inserted, which cooling element is placed on the skin to cool it and numb it prior to the injection.
The present invention improves upon the teachings of the prior art described above by providing a simple spraying mechanism for spraying a topical anesthetic onto the skin where an injection is to take place using a disposable and sometimes pre-filled syringe.